Air compressor



Aug. 11, 1936. H HATMAKER 2,050,886

AIR COMPRESSOR Filed Feb. 6, 1955 ATTORNEY Patented Aug. 11, 1936 'aosoisst AIR, COMPRESSOR Howard Hatinaker, Tainaqua, Pa.

Application February 6, 1935, serial No. 5,254

4'Claims.

This invention relates to new and useful improvements in air compressors and the like, and it is among the objects thereof to provide a compressor, operated by fluid pressure, developed by a relatively small hydraulic unit such as a fluid pump, which may be driven by a fractional horsepower electric inotor or small gasoline engine, thus rendering it available for use in isolated places, and it is among the objects thereof to provide a compressor of simple, compact construction, embodying novel piston construction and valves and control mechanism therefor which shall render it highly e'flicient in operation.

These and other objects of the invention 'will become more apparent from a consideration of the accompanying drawing constituting a part hereof in which like reference characters designate like parts and in which:

Fig. 1 is a front elevational view partially in section of a compressor embodying the principles of this invention;

Fig. 2 a vertical sectional elevational view of a conventional form of gear pump employed in the structure shown in Fig. 1; and

Fig. 3 a front elevational view of the pump and motor drive for delivering fluid under pressure to the compressor cylinders.

In the drawing, the numeral 1 generally designates a pressure tank which is of spool shape as shown at 2, the tank being constructed in sections joined at flanges 3 which constitute reinforced ribs. Tank i is provided with inlet passages 4 communicating through conduits 5 with discharge ports 8 of a pair of cylinders 1, ball valves 8 being interposed'in the port passages "6 to permit the passage of compressed air fluid from cylinders 1 to tank I while preventing reverse flow from the tank to the cylinders. Intake ports 9 are provided in the cylinders communicating by a valved passage ID with filtering screens ll, spring biased valves l2 b'ein'g provided to prevent the egress of pressure through passage on the compression stroke of the compressors. Tank I is further provided with a service line or conduit I3, a pressure gage M, and a blow-off valve [5, the latter being adjustable by the screw l5 and wing nut I! to maintain predetermined pressures in tank I, the degree of compression of a coil spring I8 determining the pressure at which valve l5 will release the fluid air from the tank I.

The operating mechanism consists of the following: Pistons generally designated by the numeral H! are disposed in cylinders I, the cylinders being mounted on a frame that is supported on a base 2|. Pistons "I 9 comprise a sleeve "22 having a flanged head integrally formed to which are secured a plurality of piston seals 23 and 25 which are disposed between the flanged end of the pistons, a disk 25 and an end plate or cap 26 held by lock nuts 21 or other suitable means. A seal between the body of sleeve 22 and cylinder 1 is formed by a packing 28 and the bottom of each cylinder is provided with ports 29 and 30. Conduits 3| and 32 connect ports 29 and 3D 'to disk valves 33 having a movable disk 34 operated by a lever 35 that is attached-to a yoke 36. Valve 33 is provided with ports 3?, 38, 39 and 40. Disk 34 is provided with ppits 4! and 42. In one position of the disk 34, ports 39 and 40 communicate with port 42 while ports 31 and 3B are cut off. In another position ports 39 and 45 are cut off and communication is established between ports 31 and 3 8.-

through the ports M of disk 34. Port 40 of the valve is connected to a reservoir or storage tank 53 containing a supply of oil or other viscous fluid, tank 43 being also connected to a gear pu'm-p 4'4 through passage 55, Fig. 2, the pump having a plurality of dellivery ports 46 connected by conduits 41 to the valves 33, one shaft of the gear pump being connected to a motor, Mia by a coupling 44b, Fig. 3.

The valve operating levers 35 are connected by the yoke '35 to time the movements of the pistons l9 by application of the fluid pressure through valves 33 and the yoke 36 is controlled in its movement by the operation of pistons 22 and the following mechanism:

eiit'encts outwardly between rollers 53 provided in the center of the yoke 36. The yoke 36 is "provided with abutting faces 54 that are en- 'ga'ged by latches '55 pivoted at 55 to the base 2|, the latches being biased by springs 51 to an upper position. The opposite end of latches 55 are adapted for engagement by lugs 58 formed on the oscillating lever 56. The operation of the above described apparatus is briefly as follows:

With the reservoir 43 filled or partially filled with oil or the like and the blow-off valve l5 adjusted for a desired pressure, pump 44 is actuated by the prime mover (not shown) and fluid under pressure is delivered through the ports 46, conduits 41 to valves 33. As one of the valve ports 4| or 42 will be in communication with the conduit 3| leading to the port 29 of the compressor cylinder, the fluid pressure developed by the pump 44 will raise the corresponding piston 22 and compress the air or gaseous fluid in the cylinder. When the pressure in cylinders 1 developes in excess of the spring acting against the ball valve 8, the latter will unseat and the compressed fluid will pass through the conduit 5 into tank I. As the piston travels upward on the compression stroke in one cylinder, the piston in the other cylinder will be lowered through its connection to the oscillating lever 50. Oscillating movement of lever will cause spring 52 to be flexed to the point where its stored energy.

will shift the yoke 36 causing angular movement of valve disks 34 to change the setting of the valves so that the cylinder connections with the fluid pump M will be changed to connect the opposite cylinder with the pressure pump, and connect the cylinder that has completed its compression stroke with the reservoir 43.

The operation of the compressor is continuous through the mechanically controlled application and release of the fluid pressure from the pump to the cylinders by the moving yoke 36 and oscillating lever 50 as described. The valves are locked during the pressure stroke of the compressor pistons by the latch members 55 and are released at the end of the structure for reversal of the valves by the lugs 58 which strike the latches to disengage the yoke 36.

By utilizing the hollow pistons 22 they can be made of less mass while maintaining strength and rigidity, thus reducing the load on the fluid motor and increasing the force of the compression stroke for a given size power unit. By utilizing the leaf spring 52 for actuating the yoke 36, the latter is shifted by What may be termed a snap action to cause a corresponding rapid adjustment or shifting of the valves 33. The mechanism is constructed to entirely eliminate the use of gears and other rapid wearing elements excepting the gears in the pressure pump which, of course, are entirely submerged in oil to reduce the erosive effect on the gear teeth.

From the foregoing description of the invention it will be apparent that a compressor of the type herein described is of simple, compact construction, can be mounted to render it transportable and can be operated economically with various types of prime movers.

Although one embodiment of the invention has been herein illustrated and described, it will be evident to those skilled in the art that various modifications may be made in the details of construction without departing from the principles herein set forth.

I claim:

1. In a compressor unit, in combination, a pair of cylinders and a pressure tank mounted on a base, pistons operative in said cylinders, an oscillating lever pivotally mounted on the base, connected at its ends to said pistons, valves controlling the application of fluid to said pistons, a pressure pump connected by conduits to said valves and to a source of fluid, said valves having a flow passage for return of the fluid from the compressor cylinders to said source, a yoke connecting the valves to render them simultaneously operative, and connecting means between said yoke and oscillating lever, means for locking said yoke during the movement of the cornpressor pistons, and means operative with the movement of the oscillating lever for releasing said yoke.

2. An air compressor or the like comprising, in combination, a pressure tank and a pair of cylinders mounted on a base, a fluid storage tank below the compressor tank, a pump connected by conduits to the storage tank and to the compressor cylinders to deliver fluid under pressure to said cylinder, valves controlling the application and return of fluid from the pump to the tank, a yoke connecting said valves, pistons in the compressor cylinders, a lever mounted for oscillatory movement on the base connected at its ends to said pistons, spring means connecting said oscillating lever and valve yoke, and means for latching said yoke, said means being responsive to the oscillating movements of the piston lever for disengaging said yoke.

3. A compressor comprising, in combination, a pressure tank, a pair of compressor cylinders mounted in spaced relation to the tank, the tank and cylinders being mounted on a base, passages connecting the cylinders and tank, an oil reservoir below said tank, pistons disposed in the compressor cylinders and joined by a lever mounted for oscillating movement on said base, a pump connected to the reservoir having connections with the bottoms of said cylinders, valves interposed between the cylinders and fluid pressure source having return flow connections with the reservoir, a yoke connecting the valves to render them simultaneously operative in controlling the application of fluid pressure to the respective cylinders, connecting means between the yoke and piston lever and latching means for said yoke, said latching means locking the yoke in one position of valve adjustment and being responsive to movements of the piston lever to release said yoke.

4.. In a compressor, in combination, a pressure tank, a pair of compressor cylinders, hollow pistons in said cylinders connected by an oscillating lever at the bottom thereof, links interposed between the pistons and the ends of the lever, a pump for supplying fluid pressure to the pistons to actuate the same, valves controlling the flow of fluid from the pump to the piston cylinders, means actuated by the piston lever for simultaneously rendering said valves adjustable to connect one of said cylinders with the pressure pump and the other of the cylinders with a reservoir and to reverse said connections in response to movement of the pistons.

' HOWARD HATMAKER. 

